Rotary tiller



FIG. 1 is a left side perspective view of a rotary tiller showing the new design;

FIG. 2 is a left side view thereof;

FIG. 3 is a right side view thereof;

FIG. 4 is a top view thereof;

FIG. 5 is a bottom view thereof;

FIG. 6 is a front thereof; and,

FIG. 7 is a rear view thereof.

The broken lines in the drawings illustrate portions of the rotary tiller and form no part of the claimed design. 

CLAIM The ornamental design for a rotary tiller, as shown and described. 